Core catcher for well drills



March 22, 1932. WELLENSIEK 1,850,434

CORE CATCHER FOR WELL DRILLS Filed May 15, 1929 L. h. WELLENS/EK INVENTOR 9 I A TTORNEY Fatented Mar. :22, 1932 neural) star PATENT creme LUUIS H. WELLMTSIEK, F HQUSTON, TEXAS, ASSIGNOE 'IO HUGHES TOOL COMPANY, OF HOUSTQN, TEXAS, A COBBOBATIGN OF TEXAS .COBE GATGHEB FOB WERE DBELS Application filed Kay 13,

My invention relates to means for engaging the core in a core drill so that the core may be broken off and withdrawn with the drill when the drill is removed from the hole.

This device is an improvement upon that shown in my .prior co-Tpending application unobstructed and not liable to be clogged in use. i

It is a further object to simplify the strucr ture of the device set cut in my prior appli cation previously referred to, and to make the device more ecbnomical to construct and 0 reliable in use.

The invention resides largely in the particular construction and arrangement of the parts making up my improved device.

In the drawings, Fig. 1 is a central longi- 5 tudinal section through a drill-and core barrel employing my invention.

Figs. 2, 3 and 4 are transverse sections taken on the planes 2-2, spectively of Fig. 1.

The core drill with which my invention is employed may be of any desired construction. I have shown a bit comprising a head 1, having a central threaded socket 2 at its upper end about the core passage 3, to receive the shank 4 of a special drillnipple 5. The hit has lateral blades 7 tocut the well hole. Flushing fluid reaches the cutters through pasages 8 in the head.

The nipple 5 is a tubular member extended upwardly a suitable distance. Its inner diameter is increased slightly at 9 to provide a shoulder, below which the inner wall is threaded to receive a core barrel 10- screwed therein.

Adjacent the lower end of the nipple" 5, is a plurality of radial openings 11, in which are fitted housings 12 for the core-engaging dogs 13. Said housings fit closely in the openings, as seen in Fig. 2, and are adapted to'be locked therein by'set screws 14. one on each 3- -3, and 44, re

1929. Serial 30. 382,645;

side of each housing. Each housing 12 has mounted therein, a transverse pin 15, upon which a dog 13 is rotatable.

Said dogs are nearly semicircular blocks fitted within slots in said housings, the rounded side being presented outwardly, and provided with central slots 16 therein to receive the lower ends of rods 18. Transverse P1115 17 through said dogs and the ends of said rods 18 provide a pivotal engagement between them. The dogs have their inner faces 19 curved transversely to some extent, as

shown in Fig. 2, to better enga e the core when they are projected inwar y.

The rods 18 are actuated through a drill collar 20 which telescopes over the nipple 5 and is slidable on said nipple. The upper end of the collar 20 has a threhded socket 21 to engage a tool joint on the drill stem. Its

lower end 22 has a plurality of longitudinal slots 24. therein to receive the upper ends of the rods 18; the lower ends of the slots having guide openings 25 therein to allow passage of said rods. The rods 18 have nuts 26 at their upper ends and a compression spring 27 on each of said rods bears at its upper end against said nut and at its lower end 7 upon a washer set upon the lower end of the slot 24.

The drill collar 20 is connected with said nipple 5 by means of radially projecting pins 28 screwed within the nipple and projecting outwardly into slots 29 in the drill collar.

I have showniour sets of pins with two pins 28 in each set, as forming the connection between the two telescoping parts. 'The slots 29 are longer than the distance between each pair of pins 28 so as to allow a predetermined amountof play of the collar longitudinally of the nipple.

Theupper end of the nipple forms a ractically fluid tight sliding connection wit the collar through the use of a ring 30 of composition fitting within a recess in the drill collar and projectng within a recess 31 in'the nipple. For purposes of assembly grooves 32 longitudinally of thenipple are formed to allow the rod and spring 18 and 27 to he moved downwardly over the said nip le; The pins 28 may he held from nscrewing by the use dogs 13 will be approximately in the posi-" tion illustrated. When the drill rests upon the bottom, however, the drill collar will slide down on the nipple to bring the pins 28 into the upper end of the slots 29 so that the weight of the drill collar and drill stem will rest upon the drill. This movement of the collar downwardly upon the nipple will release the upward tension upon the springs 27 and will allow dogs 13 to rotate into a position with their inner faces parallel with the inner wall of the core barrel.

The rotation of the drill stem will then be communicated through the pins 28 to the nipple and drill and the hole will be cut and a' core will gradually project upwardly into the core barreL- When it is desired to bring the core to the surface the drill will be withdrawn. The upward movement of the drill collar will bring the pins 28 to the bottom of the slots 29 as shown in Fig. 1, and will exert a compression upon the springs 27 to pull the rods 13 upwardly and move the core engaging dogs into the position shown, the dogs then being .brought into contact with the core. If the core is of soft material, the dogs will penetrate the core to the dotted line position in Fig. 1, but where the not penetrate so deeply. This .will break of! *the core and carry it along with the core barrel.

It is to be noted that the pull upon the rods to move the dogs is entirely: through the springs 27. and there will be no danger of too great a pull upon the rods whereby they might be broken or the nuts 26 stripped from the rods as might otherwise happen. Furthermore, in this embodiment, the parts are nipple, radial pins on said nipple'projecting easily "accessible for assembly or disassembly when necessary. The springs and rods 27 and 13 are exposed so that they maybe washed clear of sand or mud tending to clog their action."

What I claim as new is:

' 1. A core bit, an upwardly vextending nipple thereon, a drill collar telescoping over said nipple, radial pins on said nipple ,projecting into openings" in said drill collar, and having a limited longitudinal play therein, core engaging dogs in said nipple, and means on said collar adapted to engage said dogs to move them into core-engaging position.

2. core bit, an upwardly extending nipple thereon, a drill collar telescoping over said into openings in said drill collar, and having a limited longitudinal play therein, core encore is hard, it will to move said rods and said nipple, a radial pin on said nipple projecting into a slot in said collar to allow a limited longitudinal movement of said collar relative to said nipple, core-engaging dogs in said nipple, and resilient connections between said collar and said dogs, whereby the movement of said collar relative to said nipple may move said dogs.

4. In a core drill, a bit, a nipple thereon, a' drill collar engaging telescopically over said nipple, a radlal pin on said nipple projecting" into a slot in said collar to allow a limited longitudinal movement" of said collar relative to said nipple, core-engaging dogs in said nipple, rods on said dogs projecting into said collar and springs on said rods engaging said collar, whereby the move- 3 ment of said collar relative to said nipple may move said dogs.

- 5. In a core drill, a drill head, a nipple connected therewith, core-engagingdogs in said nipple pivotally mounted in said nipple.

means to rotate said nipple and bit, and means on said rotating means resiliently connected with said dogs, the weight of said rotating means acting to hold said dogs depressed, whereby said dogs may be pivoted to move inwardly to engage the core when said rotating means is moved upwardly.

said nipple; a plurality of radial pins detachably mounted in said nipple and projecting into slots in said drill collar to allow a limited longitudinal play between said nipple and said collar and means actuated by said longitudinal movement of'said collar relative to said nipple to move inwardly to engage the core. a

8. In a core drill, a drill bit, a nipple thereon, a dull collar telescopically engaging said nipple to communicate a rotation thereto,

core engaging dogs pivotally mounted in and nipple to move inwardly, to engage the -core, rods on said'dogs slidably engaging said drill collar, and springs on said rods adapted to be compressed to exert a pull on said rods. I

9. In a core drill, a drill bit, a nipple thereiao nsaaaaa on, core engaging dogs in said nipple, a. drill collar telescopically engaging said nipple, said collar having longitudinal slots therein, pins adapted to be inserted through said slots to engage within said nipple, and means on said collar engaging said dogs to move said dogs in said nipple.

10. In a core drill, a drill bit, a nipple member thereon, a collar member telescopically engaging with said nipple member, means engaging said nipple and collar together to allow a limited play longitudinally between them, core engaging dogs on one of said members, and means on the other said v member resiliently connected withsaid dogs to move said dogs into core engaging posltion.

11. In a core in, a drill head, a drill collar telescopically engaged therewith to drive said drill head and having a limited longitudinal movement relative thereto, dogs pivoted on axes transversely of said head, means on said collar engaging said dogs to cause them to pivot on their axes when said collar is moved longitudinally relative to said head, so as to move said dogs to and from core engaging positi0n.-

12. In a core drill, a head member and a drive collar member having a limited tele .scopic movement longitudinally and held to said collar so as to be projected into core engaging position by the vertically upward movement of said collar relative to said head While said head-is stationary.

14. In a core drill, a drill head, a drive collar connected to drive said drill head, but

having alimited longitudinal play relative to said head, core engaging dogs pivotally supported on horizontal axes set in said head,

and means connecting said dogs with said collar whereby said dogs are forced into core engaging position by the relative vertically upward movement of-said collar.

In testimony whereof I hereunto aflix my signature this 10th day of May, A. D. 1929. LOUIS H. WELLENSIEK. 

